There may be many reasons a load such as an aircraft will not accept external power from an external aircraft power supply cart, hanger power, or other power supply. The power supply may be non-optimal, but generally a replacement power supply is tried or a support equipment supplier diagnoses the power supply. Sometimes, there is a problem with load power system monitoring equipment or load wiring/circuitry. There are cases where the load power system monitoring equipment has failed due to an anomaly, and been replaced with a new part which also failed due to a problem with the load wiring/circuitry. This process is tedious, takes time and resources, and sometimes results in inaccurate conclusions.